linux-kernel - [PATCH v4 06/15] futex2: Add compatibility entry point for x86

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  3 Jun 2021 16:59:15 -0300
From:   André Almeida <andrealmeid@...labora.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Darren Hart <dvhart@...radead.org>,
        linux-kernel@...r.kernel.org, Steven Rostedt <rostedt@...dmis.org>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc:     kernel@...labora.com, krisman@...labora.com,
        pgriffais@...vesoftware.com, z.figura12@...il.com,
        joel@...lfernandes.org, malteskarupke@...tmail.fm,
        linux-api@...r.kernel.org, fweimer@...hat.com,
        libc-alpha@...rceware.org, linux-kselftest@...r.kernel.org,
        shuah@...nel.org, acme@...nel.org, corbet@....net,
        Peter Oskolkov <posk@...k.io>,
        Andrey Semashev <andrey.semashev@...il.com>,
        Davidlohr Bueso <dave@...olabs.net>,
        André Almeida <andrealmeid@...labora.com>
Subject: [PATCH v4 06/15] futex2: Add compatibility entry point for x86_x32 ABI

New syscalls should use the same entry point for x86_64 and x86_x32
paths. Add a wrapper for x32 calls to use parse functions that assumes
32bit pointers.

Signed-off-by: André Almeida <andrealmeid@...labora.com>
---
 kernel/futex2.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/kernel/futex2.c b/kernel/futex2.c
index 1e97e5f2e793..5fd0b3d73b53 100644
--- a/kernel/futex2.c
+++ b/kernel/futex2.c
@@ -23,6 +23,10 @@
 #include <linux/syscalls.h>
 #include <uapi/linux/futex.h>
 
+#ifdef CONFIG_X86_64
+#include <linux/compat.h>
+#endif
+
 /**
  * struct futex_key - Components to build unique key for a futex
  * @pointer: Pointer to current->mm or inode's UUID for file backed futexes
@@ -910,7 +914,16 @@ SYSCALL_DEFINE4(futex_waitv, struct futex_waitv __user *, waiters,
 	futexv->hint = false;
 	futexv->task = current;
 
-	ret = futex_parse_waitv(futexv, waiters, nr_futexes);
+#ifdef CONFIG_X86_X32_ABI
+	if (in_x32_syscall()) {
+		ret = compat_futex_parse_waitv(futexv, (struct compat_futex_waitv *)waiters,
+					       nr_futexes);
+	} else
+#endif
+	{
+		ret = futex_parse_waitv(futexv, waiters, nr_futexes);
+	}
+
 	if (!ret)
 		ret = __futex_waitv(futexv, nr_futexes, timo, flags);
 
@@ -1215,6 +1228,27 @@ SYSCALL_DEFINE6(futex_requeue, struct futex_requeue __user *, uaddr1,
 	if (ret)
 		return ret;
 
+#ifdef CONFIG_X86_X32_ABI
+	if (in_x32_syscall()) {
+		ret = compat_futex_parse_requeue(&rq1, (struct compat_futex_requeue *)uaddr1);
+		if (ret)
+			return ret;
+
+		ret = compat_futex_parse_requeue(&rq2, (struct compat_futex_requeue *)uaddr2);
+		if (ret)
+			return ret;
+	} else
+#endif
+	{
+		ret = futex_parse_requeue(&rq1, uaddr1);
+		if (ret)
+			return ret;
+
+		ret = futex_parse_requeue(&rq2, uaddr2);
+		if (ret)
+			return ret;
+	}
+
 	return __futex_requeue(rq1, rq2, nr_wake, nr_requeue, cmpval);
 }
 
-- 
2.31.1